JPH0738301A - Cross circuit of strip line - Google Patents

Abstract

PURPOSE:To obtain the circuit which can execute crossing of two pieces of strip lines by the same layer, can facilitate the wiring of a multilayer printed board, and can reduce the number of layers by connecting all nodal points by a 1/4 wavelength line in the cross circuit of two inputs and two outputs. CONSTITUTION:A first input nodal point IN1 to which a first input signal is inputted is connected by a 1/4 wavelength line to a first and a second nodal points N1, N2, respectively, and a first nodal point N1, and a second nodal point N2 are connected to a second input nodal point IN2 and a fifth nodal point N5, respectively by the 1/4 wavelength line, and to a second output nodal point O2 and a fifth nodal N5, respectively by the 1/4 wavelength line, respectively. In such a way, by constituting this circuit so that each nodal point N1-N5 is all connected by the 1/4 wavelength line, a first and a second input signals of the same frequency inputted to a first and a second input nodal points IN1, IN2, respectively appear only in a first and a second output nodal points O1, O2, respectively, and are outputted as a first and a second output signals, respectively. In such a way, two pieces of strip lines can be subjected to level crossing by one layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stripline crossing circuit, and more particularly to a stripline crossing circuit in a multilayer printed circuit board used in a portable radio communication device or the like.

[0002]

2. Description of the Related Art Multilayer printed boards are widely used in high frequency circuits such as portable radio telephones. The multilayer printed board can be provided with component mounting patterns on the upper and lower surfaces of the board and wiring patterns on the inner layer, which greatly contributes to downsizing of the high frequency circuit (Japanese Patent Laid-Open No. 63-308999).
JP-A-3-129895).

In such a multilayer printed board, when the wirings are crossed with each other, it is necessary to provide a space between the wirings so as not to be AC-coupled to each other.

FIG. 5 is a schematic perspective view showing an example of a conventional cross circuit of inner layer strip lines. As shown in the figure, when the two lines 101 and 102 intersect in a certain layer L1, the line 101 is connected to the other layers through the through holes 103 and 104 so that one line is not AC-coupled with the other line. L2 is connected to the line 105, and the other line 10
A grade separation structure that bypasses the lower or upper layer of No. 2 was adopted.

[0005]

However, in the above-described conventional crossing circuit, the number of layers of the multilayer printed board increases, and the wiring of the lower layer L2 is also limited. Further, since one inner layer strip line is divided into a plurality of layers for wiring, the route becomes complicated and it becomes difficult to form the wiring.

Therefore, an object of the present invention is to provide an intersecting circuit which allows two strip lines to intersect each other in the same layer to facilitate wiring of a multilayer printed board and reduce the number of layers.

[0007]

According to the present invention, in one layer of a multilayer printed board, a first signal inputted to a first input node is outputted from a first output node and inputted to a second input node. It is a stripline crossing circuit in which the second signal of the same frequency is output from the second output node.

That is, the first input node and the first node and the first node and the second input node are respectively connected by a quarter wavelength line, and the first input node and the first input node are connected. The second node and the second node and the second output node are respectively connected by a quarter wavelength line, and the second node
Between the input node and the third node and between the third node and the first output node are respectively connected by a ¼ wavelength line, and between the first output node and the fourth node and between the first node and the third node. The four nodes and the second output node are connected to each other by a quarter wavelength line, and the first node and the fifth node are connected to each other and the fifth node and the fourth node are connected to one another, respectively. A four-wavelength line is connected, and the second node and the fifth node and the fifth node and the third node are respectively connected by a quarter-wave line. To do.

[0009]

The first signal input to the first input node appears only at the first output node, and the second signal input to the second input node is the second signal.
Appears only at output nodes.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic circuit diagram showing the construction of an embodiment of a cross circuit according to the present invention.

In the crossing circuit shown in the figure, the distance between nodes is 1 /
It has a configuration of being connected by a four-wavelength (λ / 4) line. That is, the first input node IN1 to which the first input signal is input is connected to the first node N1 and the second node N2 by ¼ wavelength line, respectively, and the first node N1 is the second input node IN2 and the fifth node N2. It is connected to N5 by 1/4 wavelength line,
The node N2 is connected to the second output node O2 and the fifth node N5 by a 1/4 wavelength line, respectively. Furthermore, the fifth node N
5 is connected to the third node and the fourth node by a quarter wavelength line, respectively, and the third node N3 is the second input node IN2 and the first node N3.
The output node O1 is connected to each of the quarter wavelength lines, and the fourth node N4 is connected to the second output node O2 and the first output node O1 to each one quarter wavelength line.

As described above, by connecting all the nodes by the ¼ wavelength line, the first and second input nodes IN1 and IN2 of the same frequency respectively input to the first input node IN1 and the second input node IN2. The input signals appear only at the first and second output nodes O1 and O2, respectively, and are output as the first and second output signals, respectively.

Therefore, the crossing circuit shown in FIG. 1 is capable of crossing two strip lines in one plane in a multilayer printed board.

FIG. 2 is a plan view of the cross circuit of the present embodiment, and FIG. 3 is a schematic perspective view showing the connection state of the strip line according to the present embodiment.

In FIG. 3, four strip lines 3 to 6 are connected on a dielectric layer 1 of a multilayer printed board by a cross circuit 2 of this embodiment. The signal S1 transmitted through the strip line 3 is transmitted only to the strip line 4 by the cross circuit 2, and the signal S2 transmitted through the strip line 5 is transmitted only to the strip line 6 by the cross circuit 2.

However, since the crossing circuit 2 has many discontinuous nodes in the dielectric layer 1 in the multilayer board, measures for thinning the wire and reducing the loss of the dielectric are taken in order to eliminate various high-frequency influences. It is desirable to apply.

Note that the present invention is not limited to the shape shown in FIG. 1, but similarly, all the nodes may be connected by a 1/4 wavelength line. For example, the shape shown in FIG. 4 is also considered. To be

[0019]

As described above, the crossing circuit according to the present invention has a 2-input 2-output crossing circuit in which every node is 1
By connecting with a / 4 wavelength line, the first signal input to the first input node appears only at the first output node, and the second signal input at the second input node appears only at the second output node Directional coupling Can be realized. As a result, the two strip lines can be made to intersect each other in a plane, and since there is no need to make a detour via another layer, the number of layers of the multilayer printed board does not increase, wiring is facilitated, and one layer is further provided. This has the effect of improving the wiring efficiency per hit.

[Brief description of drawings]

FIG. 1 is a schematic circuit diagram showing a configuration of an embodiment of a cross circuit according to the present invention.

FIG. 2 is a plan view of a cross circuit according to the present embodiment.

FIG. 3 is a schematic perspective view showing a connection state of strip lines according to the present embodiment.

FIG. 4 is a schematic circuit diagram showing the configuration of another embodiment of the cross circuit according to the present invention.

FIG. 5 is a schematic perspective view showing an example of a conventional cross circuit of inner layer strip lines.

[Explanation of symbols]

 1 Dielectric Layer 2 Crossing Circuit 3 Strip Line 4 Strip Line 5 Strip Line 6 Strip Line IN1 1st Input Node IN2 2nd Input Node O1 1st Output Node O2 2nd Output Node N1 1st Node N2 2nd Node N3 3rd Node N4 4th node N5 5th node

Claims (2)

[Claims] 1. A first signal of a desired frequency input to a first input node is output from a first output node, and a second signal of the same frequency input to a second input node is output from a second output node. In an output stripline crossing circuit, the first input node and the first node and the first node and the second input node are respectively connected by a quarter wavelength line, One input node and the second node and one of the second node and the second output node are connected by a quarter wavelength line, respectively, and between the second input node and the third node and The third node and the first output node are respectively connected by a quarter wavelength line, and the first node and the fourth node are connected and the fourth node and the second output node are connected. Are connected by a 1/4 wavelength line, respectively, and the first node and the fifth node And between points and between said fifth node and said fourth node are connected to each 1/4 wavelength line,
A strip line crossing circuit is characterized in that the second node and the fifth node and the fifth node and the third node are connected by a quarter wavelength line, respectively. 2. A crossing circuit of inner layer strip lines in a multilayer printed circuit board, wherein the first input node and the first node are connected to each other, and the first node and the second node are connected to each other.
The input nodes are connected to each other by a 1/4 wavelength line, and the first input node and the second node are connected to each other and the second node and the second output node are connected to each other to a 1/4 wavelength line. , Between the second input node and the third node, and between the third node and the first node
The output nodes are connected to each other by a quarter-wave line, and the first output node and the fourth node are connected to each other and the fourth node and the second output node are connected to each other a quarter-wave line. The first node and the fifth node and the fifth node and the fourth node are connected by a quarter wavelength line, respectively.
A strip line crossing circuit is characterized in that the second node and the fifth node and the fifth node and the third node are connected by a quarter wavelength line, respectively.